Looking for His glorious appearing! Titus 2:13

WASHINGTON -- Without committing ground troops to the cause, a coalition led by the United States against Islamic State militants in Iraq and Syria is a "ridiculous" enterprise, Iranian President Hassan Rouhani said on Wednesday.

Rouhani made the damning comments to NBC News the same day senior Iranian and US officials met privately in New York over its nuclear program, and as US President Barack Obama, in Florida, recommitted to a campaign against Islamic State exclusively using air force alone.

"I want to be clear," Obama said from MacDill Air Force Base. "The American forces that have been deployed to Iraq do not and will not have a combat mission."

Also on Wednesday, the Republican-led House of Representatives voted to approve the president's plan to arm and train vetted Syrian rebels to fight Islamic State until December 11. The Senate is expected to vote swiftly on the measure.

In the NBC interview, Rouhani suggested the US government is cowardly to commit to "unmanned" air power without the combat forces required to eliminate the group, which he agreed is an inhumane terrorist organization.

"Are Americans afraid of giving casualties on the ground in Iraq?" Rouhani asked. "Are they afraid of their soldiers being killed in the fight they claim is against terrorism?"

"If they want to use planes and if they want to use unmanned planes so that nobody is injured from the Americans," Rouhani said to journalist Ann Curry, "is it really possible to fight terrorism without any hardship, without any sacrifice? Is it possible to reach a big goal without that? In all regional and international issues, the victorious one is the one who is ready to do sacrifice."

Throughout the Iraq War of the last decade, Bush administration officials accused the Iranian government of targeting and facilitating the targeting of US troops. Tehran denied direct involvement in the fight.

Rouhani also said that air strikes in Syria required the permission of the Syrian government– the embattled regime of Bashar Assad, specifically, which the Iranian and Russian governments support. And he said that Sunni insurgent control over Baghdad and southern Iraqi territories was a "red line" for his government.

Both Moscow and Tehran have said action in Syria without Assad's permission would constitute a violation of international law, and an act of aggression. Washington has ruled out collaboration with Damascus or Iran in its fight against Islamic State.

On Capitol Hill, as the House was passing authorization for arming in Syria, US Secretary of State John Kerry testified before the Senate Foreign Relations Committee, touting the breadth of the US-led coalition.

Nations in the Middle East and Europe have committed to contribute air power to the fight, Kerry said. But the US has not asked any nation to commit combat troops.

Air strikes conducted thus far by the US military, however, have proven to be "astonishingly" accurate, Kerry told the panel. He repeated US President Barack Obama's commitment to refrain from sending ground forces.

"No country has been asked to put boots on the ground," he said, but added: "the United States will not go it alone."

Bilateral talks between senior US and Iranian officials in New York concern Iran's nuclear program exclusively, US officials said, and will continue through Thursday.

Full negotiations will begin with officials from the United Kingdom, France, Russia, China and Germany on Thursday.

"The nuclear issue is so huge in its consequences," it cannot be conflated with the fight against Islamic State, Kerry said in his testimony.

"Strange bedfellows," however, are inevitable, he added.